Shadow and Light
by Senket
Summary: Gon is light and Killua is a shadow, and no shadow can live in the light for long. At least that's what Killua tells himself. Alluka might... be smarter than him. or, Killua and Alluka visit Gon on Whale Island


Killua was born in darkness. Killua has lived in darkness, and he has always expected to die in darkness, like the rest of his family.

Gon is light. He is brimming with it, sunshine beams from his eyes, his smile. His enthusiasm is as boundless as the sky, his thirst for adventure moves him like the wind

Killua is a dark, deep lake in the depth of an underground cavern, cold and stagnant, while Gon is an ocean, waves brimming with sunlight.

They never belonged together. Killua has always known he was borrowing time.

_' Let me stay with you a little longer.'_

Eventually the sunlight would burn the shadow away.

"Ne, onii-chan?"

"Hm?"

Alluka grins up at him, her small hands fisted around his sleeves. He pushes his chair back so he can face her properly and she takes that opportunity to climb up into his lap. "You know, I like it a lot when it's sunny! The shadows are really strong!"

"...Eh?" He reels back a bit, fingers scurrowing through his white hair. "What do you-?"

"Look!" She points out the window, and when Killua keeps watching her instead of following her lead, she jumps up again and runs over to it. She pushes it open and leans her upper body out of the window, grinning in the breeze. Killua is beside her in a flash, pulling her back inside. The sun blazes above them, bouncing off the whitewashed little houses that line the coast, shadows leaving black swathes where the townspeople nap in rope hammocks.

"Ne…" Killua turns his attention to Alluka again. Her expression is thoughtful as she looks out the window, more carefully this time, her chin propped on the windowledge. He brushes his fingers through her long hair, and she tilts her face to watch him, cheek pressing against wood. "It's been a while since we saw Gon. We should visit him!" She throws her hands up into the air, and then around his neck, grinning.

Something cold and slimy twists inside him. He tucks his nose into her hair, squeezing his eyes closed. Breath twists inside him, turns hot and poisonous, burning on its way out of his throat and nostrils. His heartbeat loses rhythm, goes too fast or too slow.

Alluka's eyes are clear and ernest, bright as the sun outside as she leans back out of the hug and squishes his cheeks. It was probably the fishing boats that made her think of Gon, dots of black against the green-white waves, and not…

"Maybe he'll catch me a giant fish, and we can be friends with it!"

He lets out a breath, and hoists her into his arms. "Let's go for a walk, ok?"

"Okaaaaaaaaay!"

Killua avoids it and avoids it and avoids it, but one day Alluka asks him if they'll go see Gon soon, because she found a stone she wants to give him - it's an opal, probably, he thinks, and when you hold it up to sunlight it looks like a blue fire blazes inside, but honestly Bisky would probably like it a lot more than Gon- and he's too tired to argue with her about it. He's quiet on the whole boat ride to Whale Island, but Alluka is so excited she leaves him mostly alone, exclaiming over the ocean creatures or, as they get closer, the birds above them, running as fast as her legs can take her and jumping in the air to try and catch low-flying seagulls.

He thinks of her, alone, at the end of a long tunnel, in a room painted in bright colors. His heart twists. He did the right thing, the right thing for all of them. Gave up a sun to save another. And if it's true that Alluka 'isn't family' to the Zoldycks, then it's because they're a long yawning shadow and she's- nothing of the kind.

If she's sunshine, he admits to himself, then nanika is the shadow, but even nanika just wants love and praise.

Even a shadow wants love.

Killua pulls his legs against his chest and hides his face against his knees. Stupid. He hurts himself even on accident.

The walk to Gon's house, punctuated by the occasional smiling local that remembers him from a previous visit, is rather short, but Killua's feet feel heavier with every step. They find Aunt Mito outside, pining laundry to a drying line. She greets Alluka first and then Killua, and he notices that, though she smiles at them, her eyes are tired.

"Is Gon home?" he asks politely, hands at his side. She shakes her head, apologetic, and asks if they're staying long, leans her head vaguely towards the jungle when he asks where her boy's gone and excuses herself to make up beds.

It's not that hard to find Gon, really. He'd already shown Killua all of his favorite places on the island back when they were twelve, and Killua has every single one of them burned into his mind. Gon is at his favorite spot of all, the massive knotted tree growing out of tepid water. He caught the Master of the Swamp here. Killua- Killua goes into zetsu without really being fully aware of it. Gon feels a thousand miles away, his expression blank as he turns his face up to the sun. He's taller now, his face longer. It reminds him of that day , the day black anger had completely overtaken Gon, and-

Gon certainly doesn't have the massive build of Gon That Could've Been, but it's close enough to that nightmare memory to make his heart heavy with dread. Has it been that long since they've seen each other?

He doesn't remember Gon being this quiet.

But then Alluka, curious as to why Killua stops running, stretches her head up and spots green shorts. "GON!"

Her excited shout scares birds into flight. Gon's head turns. For a moment, his eyes are empty, blank, and darkness wells up in Killua's heart, but then he spots them and his laughing smile is so bright it washes away everything.

"It's so boring here."

The buzzing of insects is loud through the open window, the summer breeze warm and spiced. Even in nothing but boxers and a half-kicked off sheet, it's too hot to sleep. He could pretend he didn't hear anything, but when he shifts his gaze from the ceiling to Gon's shape in the bed, he catches a pair of luminous golden eyes.

"Sorry." His shrug is halfhearted.

Gon climbs off the bed- hands first, like a four-legged animal, and Killua is reminded that Gon learned Zetsu long before the word 'nen' had ever entered their world. He stretches out next to Killua on the floor, tucking an arm under his head. If Killua turned to face them their knees would knock. He doesn't. They watch each other in the darkness, and Killua wonders if Gon can feel the tension between them, or if it's just him. Him, suffocating, and Gon, blissfully unaware.

"I want to go with you. And Alluka." It sounds like an afterthought.

"I can't watch both of you."

"I don't need watching!" Gon jumps to his feet and stomps over to the window, sticking his head out into the breeze. It ruffles his dark spikes. Even the wind loves Gon. His cheeks look darker in the moonlight, and he has that line between his eyebrows he gets when he's mad. Killua's face pinches. This isn't what he wants.

He's not sure what he wants.

"It's too dangerous."

Gon turns, his hands on his hips, a silhouette framed by the windowpane. Killua can't see his expression, but he can guess it. "Plenty of people survive in the world without nen!"

He sits up, scrubbing at his eyes. He can't see Gon's face but Gon can see his, which is an unfair advantage. "Plenty of people don't run headfirst into danger every chance they get," he replies bitterly, leaving me behind to clean up all the mess.

In his nightmares the black streams of Gon's loss-injected nen eat into Gon's body until Killua is carrying nothing but a twisted skeleton, curled white bone-knuckles dripping with blood. He stares at the floor. The room is silent. Did the crickets outside get louder? He can barely hear Gon breathe.

Gon moves, and Killua lies back down, pulling the sheet back over his bare shoulder and turning on his side so that his back faces Gon. It's pointless, though, and he should've recognized that. Nobody knows Gon's stubborn streak quite like him. (or Aunt Mito, his mind helpfully supplies, and he scowls.) Gon grabs him and turns him onto his back, sitting on top of his chest and glaring down at him. He's heavier than he used to be, something that Killua must've known but something his body hadn't understood yet. It's not that he's trapped but he can't move. Gon pushes him down with his forehead, his eyes blazing, too close. "I'm not a stupid kid anymore."

Killua grits his teeth. He shoves Gon off him- too hard. It sends the teen flying into the wall. He jumps to his feet immediately, teetering on running to check on Gon or jumping out the window, and his indecision sticks him on the spot long enough for Gon to shakily get back to his feet. Gon wipes a thin trickle of blood from his elbow, glaring, and dread pools black and oily into Killua's gut. "Yes you are!" he shouts back, because Gon makes him stupid, and being stupid is easier than being weak. And being mean is easier than hurting, as if he's not hurting all the time, as if leaving Gon behind didn't rip something out of him, as if he even understood what living was before he had Gon and-

And.

"I can't watch you die."

It slips out of him quietly, a little dagger pulled out of his heart, and without it all the blood spills out. If Gon notices, he doesn't say so. But what did Gon notice about him, when his face was perpetually turned to the next wonderful thing?

"I won't die." Gon says it like it's nothing, like it's as simple as that, like Killua didn't have to carry him through the woods, his legs aching and his nen drained to nothing, knowing that if he stopped too long even to breathe then Gon might never open his eyes again. Like he didn't choose to give up his entire future to defeat Neferpitou without even allowing Killua the option to help. Like he didn't leave him behind without a thought.

"You don't know that." His voice is harsh. "You can't know that, idiot!"

They're spared from further argument when the door opens. "Oniichan? Gon?" Alluka is rubbing sleep from her wet eyes. "Wooaaaa! Gon is hurt!" She flutters over to him like a bird, touching his elbow. The fight drains from him and Killua drops back down to the futon, drained. He hangs his head, watching Alluka and Gon through his hair.

Gon switches instantly from angry to big smiles. "It only hurts a tiny bit. See?!" he flails his arm about animatedly. Alluka laughs, clapping her hands together.

"Were you practicing fighting?"

"Yep!" Gon pats her head. He's good with her. It's because they're both children, Killua thinks bitterly. He loved that about Gon- when they were 12 and Gon was his first friend. Now it rankles. Gon is a light, and he will always be a light, but Killua can't chase dragonflies forever when he always ends up with empty hands.

"Come on, Alluka, let's go back to sleep." He becons her with a hand movement. "It's too late to practice fighting anyway."

"It really is! Silly oniichan!"

She wanders to him and climbs into his arms. He pulls the cover around both of them and tucks his nose into her long hair. "Good night Oniichan!" she giggles. "Good night Gon!"

"Good night, Alluka," says Gon in a carefree voice. Killua wishes he could turn off his anger like that, too, but he can't. He never could.

"Take me with you."

"No."

"I won't die."

"You're famous. Even if you didn't chase danger-" which, hah- "it chases you."

Gon shrugs, planting his hands on his fists again. "You'll be there."

He's sick of this game. He's sick of this feeling. He's- he's just sick, and he needs to get off Whale Island, and he wants to forget he came. "I can't protect you all the time."

"Why not? You do it for Alluka!"

Killua flushes, irritated. Gon's stubborn streak is remarkable, everyone knows that. His arguments are incessant. And also, stupid.

"Alluka isn't always running ahead."

"I'll stay by you then!"

"And when we find danger?"

"I'll stay with Alluka while you take care of it!"

"I can't always-"

"Yes. You can."

Killua ducks his head. He can feel something welling up that he doesn't want the other boy to see. His hands clench at his side. He's helpless in the face of Gon's conviction. Warm, rough hands close against his arms. He twists his head to the side. "Yes, you can." Gon's voice is softer now. "I trust you."

"I-" He shudders. Words of indefinite shape clog his throat. Too many things want to get out, and too many other things can't. He can't stay here much longer, in this place he doesn't belong, not when the dull ache is starting to awake again. They've been here three days (had this argument five time) and every time he lifts his head to find Gon, every time he realizes that he's been doing that every day they've been apart, it burns a little more.

"Please."

"Gon, I can't."

"I want to go with you."

He wants to travel. He wants to leave Whale Island. He's bored. He craves adventure. He wants to run free. Killua can give that to him. Killua is a good memory for him. Excitement.

Killua isn't a travel pass.

He shakes his head, his mouth pressed into a thin line.

"Please, Killua." There's a softness he's doesn't remember ever hearing in Gon's voice. He lifts his head and when their eyes meet there's a sadness he's not sure he's ever seen. Gon's grip on him loosens, the young man's fingers leaving traces of heat against his skin as they slip down his arm and lightly coil around his wrist. Fingertips touch against his cool palms, and a part of him flares with the wish that the touch could leave the whorls of fingerprints burned into his skin. "I want to be with you."

Killua's body jerks away on impulse. He twists, but Gon's hands tighten around him in a flash. His face contorts, mouth pulling flat, then stretching back from his teeth. The sounds he makes are inhuman, the highpitched emanations of a small, tortured animal. Gon pulls him forward and wraps his arms around Killua's shoulder, holds on with a grip that brokers no argument. Killua twists and turns but he won't hurt Gon and Gon knows it, and Gon holds on. He can't get out. He can't escape. He can't. Hide.

He can't hide. Gon always does this. He blasts all the shadows away and leave him exposed.

He's not usually looking at Killua when that happens. But now he is. "Stop it!" But Gon doesn't stop. He holds on until Killua can't fight anymore, until he slumps against Gon. Until his trembling hands press against the boy's back, his wet eyes pushed into Gon's shoulder. Gon who, he belatedly realizes, having avoided being so close to him until now, is actually taller than him.

But Gon just strokes his hair and turns his head so that his nose is right above Killua's ear, and all he says is: "Please."

They leave on the morning of the sixth day. Mito comes down to the docks to wave goodbye, her expression half-worried half-relieved.

"Ahhh! Oh no!"

Killua cranes his head to look at Alluka. Her eyes are wide, and she has both her hands pressed against her mouth. "What's wrong?" he asks, ruffling her hair.

"I got so excited I forgot to give Gon the stone I found for him!"

Killua pauses, sighs. It's his own fault. He forgot, too. He bends down to his backpack, fishes through one of the pockets to hand her the little gem. She accepts it with a beaming smile- "Thanks oniichan!"- and runs over to the bow of the ship. Gon is sitting on the railing, beaming up at the seabirds, kicking his feet as he laughs. He accepts the gift from Alluka with a gracious grin. He inspects it for a moment or two in his palm. Alluka says something he can't hear, and Gon nods Very Seriously. He stands up on the bow- Killua starts forward, half expecting the idiot to fall right into the ocean, and holds the opal between his thumb and forefinger.

"That's so cool!" He hears Gon exclaim as he gets closer.

Gon is in full sunlight, his arm stretched above him as if he's offering the opal to the sky. His eyes are full of wonder, sparking gold, alive. Killua stumbles to a stop, flushed, taken aback by the blast of energy that is a happy Gon-

It throws the low-energy smiles of Whale Island into stark relief-

And-

There's an added quality to Gon's smile as he looks at the gem that Killua really doesn't understand. Light reflecting off the ocean waves dances on Gon's face, as if the light is pouring out of him, and he says-

"It reminds me of Killua!"


End file.
